Go SLOWLY.
Even if you're a good runner and take marathons in your stride you will still spend most of the MdS at a fast walking pace or a very slow shuffle. It's not a race where physical condition is paramount, it's more about conservation of energy and water, and management of the damage you do to your body. As a first timer your aim should be to finish the event; it's too easy to go a little bit too fast and wreck your feet or overheat and get put on an IV.
Incidentally, as you will be going long and slow, you burn body fat at a high rate, so don't turn up at the start line with a ripped six-pack (if only...) you need to have 7-10lb to lose so aim to be bit fatter than you would be for, say, an important road marathon.
Include walking in your training schedule.
You need to be used to the movement of fast walking, it puts different strains on your legs and feet to running. A multi-day walking holiday would be ideal with a rucksack and trail shoes.
Take care of your feet.
The sweatier your feet are the worse you'll cope. Take several pairs of nice new soft running socks and change them frequently, I got into the habit of changing at each check point. It takes a couple of minutes but it's worth it. Just swap between two pairs and keep letting the spare pair dry out. For shoes, I had a pair of the New Balance MdS (1100s I think) and they were excellent. Strong and supportive like a trail shoe but very well cushioned like a road trainer. They don't breathe well though (because they are sand-proof) and you need to balance sweatiness with protection. I just took cheap socks from Decathlon; new and soft is more important than highest quality because you'll throw them all away as the race goes on anyway. Some people took toe-socks (Jininjis?) but I don't think they made a lot of difference and once you've got a few blisters you can't get them on over the dressings anyway.
Take oversized shoes
This is the most common bit of advice you'll find on the MdS. You can't tell how much your feet will swell until you're halfway through the week, and to make things worse they can swell differently in different years' races! My advice would be to take a pair that you can run in without them moving around too much but the sides of your toes don't make contact with the inside of the shoes at any point when wearing normal, cushioned type running socks. Take thinnish socks for the race and one super-thin, silk or synthetic pair just in case. You could also take a thickish pair for the first stage and bin them afterwards. Incidentally, my local running shop (Alexandra Sports in Portsmouth; an excellent shop) told me that I should be wearing a size larger than my 'civilian' shoes anyway, so if the brogues are a size 41 then I should run normally in trainers size 42 and for the MdS I should consider size 43. As it was, the pair I took were size 42 and I was OK, but I have particularly non-sweaty feet.
If they're a bit big then it might be inconvenient, but if they're too small then you will either endure some serious misery or DNF.
Wear gaiters.
If your feet don't sweat much then use the sand-baggers parachute silk type and glue them onto your shoes with Shoe Goo (This is by far the best stuff). Take a spare tube with you and some Duck Tape for temporary reinforcements at toes and heels. If you have sweaty feet then you might be better off with the RaidLite lycra ones - these aren't as sand-proof as the silk ones but let your feet breathe better. These work best with velcro, which you should get stiched and shoe-gooed to your shoes by a cobbler. Train with a bit of sand in your shoes.
Take LOTS of painkillers.
You can take the maximum dose of ibuprofen at the same time as paracetamol. Plan to be able to dose up for 8 hours a day for 6 days and you'll have enough. I never take painkillers in daily life but during the MdS even the luckiest first-timers (I counted myself amongst these) still get blistered and bruised feet; having the painkillers means you can ignore the pain better, keep a better running style and not cause yourself muscle and ligament problems by hobbling.
Weigh your kit...
It should not go over 10kg, and ideally you should aim for nearer 7kg. Next time, other than what's on the minimum kit list I will take more peanut M&Ms and other nut/fruit mixes and less expedition food. Look for high fat foods to carry. The Esbit cookers are OK but a bit heavy, you can just use the fuel packs and make a little fire each night from stones. 3 - 5 packs of Esbit fuel should be enough to cook all your food and to make a few cups of tea. Some people took MSR petrol fuel stoves, which are light, since you can get petrol in the town before gong out to the desert. Order some Esbits just in case though.
...But take enough kit to be comfortable.
Essential 'luxuries' are a good sleeping mat, (you need your sleep!) and a pair of flip-flops or Crocs to give your feet a chance to recover. Crocs could even be pressed into service if you cannot get your shoes on or they break. Take a warm top for the night stage (I found 3C far worse than 50C!), a windproof (the white paper suits are very practical, if geeky. I didn't have one and will still take a pertex instead, but others swear by them). Take two Buffs, long and short leggings and a tiny digicam or disposable camera.
Don't take energy drink powder.
Make your own mind up about this because I know for one Lucy would strongly disagree, but drink mixes are heavy and DONT COUNT towards your 2000 cals/day. Gels and bars do count so take these (and nuts) instead. Some people like the Nuuns isotonic tablets but you stil need the salt the medics hand out or you can suffer. When you get a salt/hydration problem it happens fast. One minute you're ok, the next you're vomiting and in the helicopter on your way to the IV and a DNF. Get used to training on water.
Take the salt tablets.
But be a bit careful. The medics don't want you collapsing and dying out in the dunes so they overdo the salt recommendation a bit, especially for first timers. Never take more than the medic say and keep a watch out for water retention in you hands and especially feet. It can make them swell and makes the blistering problem very much worse. I took three per 1.5l bottle and found I was OK. Don't be tempted to reduce the salt tabs just because you have isotonic drink.
Finally, don't go to race.
It's nice to do your best of course, but far better to finish slow than to fail fast. The MdS is so much more than a race, it's an amazing experience of vast landscapes, glittering skies and a feeling of camaraderie that is so uplifting that you will forget the pain and never want to leave. You don't want to cheat yourself by missing out on finishing. Go to learn and if, like me, you get the desert in your blood, go back to race another year armed with your new experience and with a finisher's medal already on the mantelpiece.
